AAVE Token
The Aave protocol is migrating from its native LEND token to the AAVE token, as detailed in Aavenomics. The AAVE token is an ERC-20 compatible token with the addition of a snapshot feature (used in governance balance tracking) and integrates EIP 2612 permit function, allowing gas-less transactions and one transaction approval/transfer.
This section will cover the technical aspects of the token and token migration. For governance, security, and incentive details, see the Aavenomics documentation.
Mainnet
When integrating, only the proxy contracts should be used.
Proxy Contracts | Address and ABIs |
The following are the current implementation of the contracts, which may be subject to change. Therefore always integrate the above proxy contracts only.
Implementations | Address and ABI |
Auditor | Audit Type |
Smart Contract | |
Smart Contract | |
Properties Verification |
The LEND to AAVE migration will occur via user initiated actions, using the
LendToAaaveMigrator contract. This can be performed in our app or by calling the LendToAaveMigrator contract directly.For each
amount of LEND migrated, amount/LEND_AAVE_RATIO of AAVE will be redeemed. The LEND_AAVE_RATIO is set at the time the contract is deployed and can be fetched by calling LEND_AAVE_RATIO() on the LendToAaveMigrator contract.When the governance proposal for the token migration passes, the
LendToAaveMigrator contract will be enabled. This is estimated to happen at Block 10978863.Since the AAVE total supply will be lower than LEND total supply, the
LEND_AAVE_RATIO must always be greater than 1, causing a loss of precision for amounts of LEND that are not multiples of LEND_AAVE_RATIO. For example, a person migrating 1.000000000000000022 LEND, with a LEND_AAVE_RATIO == 100, will receive 0.01 AAVE, losing the value of the last 22 units of LEND. For more details on the reasons for this approach, see the Github repo.function migrateFromLEND(uint256 amount) externalMigrates a certain amount of LEND to AAVE.
The user must
approve() the amount for the LendToAaveMigrator contract to migrate, before execution.Parameter | Type | Description |
amount | uint256 | The amount of LEND to be migrated |
function _totalLendMigrated() view publicReturns the total amount of LEND that has been migrated to AAVE.
Return Parameter | Type | Description |
_totalLendMigrated | uint256 | The amount of LEND already migrated |
event LendMigrated(address indexed sender, uint256 indexed amount)An event emitted when a
migrateFromLend() executes successfully.Parameter | Type | Description |
sender | address | The owner of the LEND and migrated AAVE |
amount | uint256 | The amount of LEND migrated |
As mentioned above, the AAVE token is an ERC-20 compatible token with the addition of a snapshot feature (used in governance balance tracking) and integrates EIP 2612 permit function, allowing gas-less transactions and one transaction approval/transfer.
Besides the standard ERC20 token features (
transfer(), balanceOf(), allowance(), etc), the following features are also available.function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) externalAllows a user to permit another account (or contract) to use their funds using a signed message. This enables gas-less transactions and single approval/transfer transactions.
Parameter | Type | Description |
owner | address | The owner of the funds |
spender | address | The spender for the funds |
value | uint256 | The amount the spender is permitted to use |
deadline | uint256 | The deadline timestamp that the permit is valid. Use uint(-1) for no deadline. |
v | uint8 | Signature parameter |
r | bytes32 | Signature parameter |
s | bytes32 | Signature parameter |
Web3.js
import { signTypedData_v4 } from 'eth-sig-util'
import { fromRpcSig } from 'ethereumjs-util'
// ... other imports
import AaveTokenAbi from "./AaveTokenAbi.json"
// ... setup your web3 provider
const aaveTokenAddress = "AAVE_TOKEN_ADDRESS"
const aaveTokenContract = new web3.eth.Contract(AaveTokenAbi, aaveTokenAddress)
const privateKey = "YOUR_PRIVATE_KEY_WITHOUT_0x"
const chainId = 1
const owner = "OWNER_ADDRESS"
const spender = "SPENDER_ADDRESS"
const value = 100 // Amount the spender is permitted
const nonce = 1 // The next valid nonce, use `_nonces()`
const deadline = 1600093162
const permitParams = {
types: {
EIP712Domain: [
{ name: "name", type: "string" },
{ name: "version", type: "string" },
{ name: "chainId", type: "uint256" },
{ name: "verifyingContract", type: "address" },
],
Permit: [
{ name: "owner", type: "address" },
{ name: "spender", type: "address" },
{ name: "value", type: "uint256" },
{ name: "nonce", type: "uint256" },
{ name: "deadline", type: "uint256" },
],
},
primaryType: "Permit",
domain: {
name: "Aave Token",
version: "1",
chainId: chainId,
verifyingContract: aaveTokenAddress,
},
message: {
owner,
spender,
value,
nonce,
deadline,
},
}
const signature = signTypedData_v4(
Buffer.from(privateKey, "hex"),
{ data: permitParams }
)
const { v, r, s } = fromRpcSig(signature)
await aaveTokenContract.methods
.permit({
owner,
spender,
value,
deadline,
v,
r,
s
})
.send()
.catch((e) => {
throw Error(`Error permitting: ${e.message}`)
})
function _nonces(address owner) publicReturns the next valid nonce to submit when calling
permit()event SnapshotDone(address owner, uint128 oldValue, uint128 newValue)An event emitted on every
transfer, mint (with a valid to address), and burn (with a valid from address).The snapshots are used for governance balance tracking.
Parameter | Type | Description |
owner | address | The owner of the AAVE tokens |
oldValue | uint128 | The value before the operation was executed |
newValue | uint128 | The value after the operation was executed. |
Last modified 2yr ago